ProgramNode(0...8)(
  [],
  StatementsNode(0...8)(
    [CallNode(0...6)(
       nil,
       nil,
       (0...1),
       nil,
       ArgumentsNode(2...6)(
         [StringNode(2...6)((2...3), (3...5), (5...6), "\\n")]
       ),
       nil,
       nil,
       0,
       "a"
     ),
     CallNode(7...8)(nil, nil, (7...8), nil, nil, nil, nil, 0, "b")]
  )
)
